Tool for removing ridges



L. o. BEARD "root, FOR REMOVING .RIDGES Sept. 18, 1934.

File'd June 26, 1953 Patented Sept. 18, 1934 UNETED STATES err-Ice 1 Claim.

My invention relates to tools for removing ridges from the walls of internal combustion engine cylinders. It is common knowledge that constant reciprocatory piston action causes the 5 cylinder walls to become gradually worn away, leaving an objectionable ridge at the top of the cylinder which interferes with proper piston action when new piston rings are installed.

The general object of my invention is to pro- 10 vide a simple form of cutting tool which can be conveniently mounted upon all types of cylinder blocks.

Another object of the invention is to provide supporting and guiding means for the cutting tool which permits of adjustments being made to compensate for blocks having cylinders of different diameters.

A still further object of the invention is to provide means for removing ridges from cylinders which are slightly out of true, without danger of forming objectionable shoulders.

The above and other and more specific objects and advantages of the invention will be apparent as the specification is considered in connection with the accompanying drawing, in which:

Figure 1 is a plan view of the cutting tool mounted upon a cylinder block;

Figure 2 is a sectional View taken on line 2-2 of Figure 1;

Figures 3 and 4 are perspective views showing the rear and front ends of the cutting blades respectively; and

Figure 5 is a plan view of the supporting clamp, with the split bushing secured between the walls of the jaws of the clamp.

Referring more particularly to the drawing T denotes the tool as a whole including a cutter head 1, having 2. depending cylindrical body portion 2, adapted to be loosely received within the bore 3 of an internal combustion engine cylinder block 4. A centrally disposed upstanding projection 6 formed on the cutter head is provided with a threaded bore 7 communicating with an axially alined larger bore 8, extending to and through the bottom of body 2. The tool T is supported in place, in a manner hereinafter described by means of a supporting and Expansion is effected by means of a beveled rotary expansion plug 13 the threaded stem 14 of which is mounted in opening '7 previously re ferred to. When the stem 14 of plug 13 is rotated in an appropriate direction, by a standard wrench or other suitable tool, not shown, the beveled face 150i the body portion 25 of the plug will be moved downwardly against the beveled inner face 16- of blades 9 thus forcing the blades outwardly into contact with the wall of cylinder bore 3. The tool as a whole is then turned approximately one revolution to the right by means of a suitable tool, not shown, applied to the hexagonal end 17 of projection 6, and this operation is repeated as often as necessary to remove the ridge 18, it being understood that the cutter blades will be slightly advanced or expanded after each revolution of the cutter head by rotation of stem 14. As previously stated a standard wrench can be used to rotate the expansion plug, the upper end of stem 14 thereof being provided with a tool engaging squared end 19 for this purpose. If desirable rotation of the tool T and feeding of the cutter blades can be simultaneously effected by the employment of two wrenches for turning the cutter head and expansion plug respectively. Of course this would necessitate the workman using both hands, one for each wrench. The tool of course should not be turned to the left or backwards. Preferably the cooperating beveled faces 15 and 16 of the expansion plug and cutters are on an angle of approximately forty five degrees to the axis of the cutter head but any angularity may be employed provided the angle is the same on each face.

It will be noted that the blades 9 are gradually tapered longitudinally, that is the blades are of decreasing thickness from their upper to their lower ends. By virtue of this increase in the diameter of the top portion of the blades, over the bottom portion thereof, unworn ridges can be removed from a cylinder Which is out of true without danger of leaving a shoulder. The high or top side of the cutting edges 21 of the cutters 9, will of course cut somewhat deeper than the low side and consequently the ridge can be completely removed without the necessity of making such fine blade adjustments as might cause a shoulder to be left or formed at or adjacent the low side. The blades 9 are also tapered laterally from the cutting edge 21 to the trailing or opposite edge 22, that is the blades are slightly thicker at the cutting edge.

Heretofore it has been proposed to provide the top portion of the body of ridge removing tools with radial arms or lugs which rest upon the top of thecylinder block and support the tool within the cylinder. However, these arms proved objectionable due to the fact that some blocks are scooped out or uneven adjacent the cylinder bores and consequently the tool would be unevenly supported. Furthermore certain of the cylinder block studs or bolts and the arms frequently interfered with each othe r According to the present invention the body 2 of the tool 1 is provided with an annulargroove 23 adapted to snugly receive the jaws 25 of a supporting clamp 26 with freedom for relative turning movement. The shank 27 of clamp 26 is formed with an elongated slot 28 through which one of the cylinder block studs 28' extends, a nut 29 and washer 30 being employed to secure the clamp in place. Adjustment toward and away from the cylinder bore 3 to accommodate for bores of different diameter can be readily efiected by loosening; nut 29 and sliding the clamp in an appropriate direction. As the shank 27 is of considerable length it can be evenly seated upon the uneven surface of a block thus securely supporting the tool against lateral or tilting movement and consequently eliminate chattering.

In order to insure a snug fit between the jaws 25 and the g'rooved'porti'on :of body 2 and *also to prevent wear on the wall of annular groove 23 the jaws are provided with a split bushing 30, the outer half of which is held in place by means of readily removable set screws 31. V. The bushing 30 will of course be snugly received in annular groove 23 thus maintaining tool T and clamp 26 in rotatable interlocking engagement with each'otherl Having thus described my invention,-

What I claim is: V

A tool for removing ridges from the top of a cylinder comprising a cylindrical cutter head having an annular groove of substantial depth in its sidewall, an elongated forked member for supporting said cutter head against axial movement having its forked end extended into the groove of said cutter head, a split bearing of less wall thickness than the depth of said groove seated Within said groove and said forked end for rotatably connecting said cutter head and forked 'member; means on the forked end of said member foradjustably and reinovably securing said split bearing to said forked member, and means in said clamping member to permit its clamping to the studs of a cylinder block and alignment of said cutter head with the cylinder to be cut.

LAWRENCE O. BEARD. 

